Solar Panel Cost UK 2026: Prices by System Size, House Type & Region
The honest answer to “how much do solar panels cost?” is “it depends” — but not by nearly as much as the quotes you’ll get suggest. This guide gives you the real 2026 prices: the national average, cost per panel and per kW, every common system size, what a 3-bed house should pay, the extra for a battery, the full installation breakdown, Scotland and Wales, the price trend before VAT returns in April 2027, and a quick calculator so you can price your own roof before anyone visits it.
Find out what your roof actually costs — from a local installer
The prices below are national ranges. A vetted, MCS-certified installer who covers your postcode will survey your roof and give you a fixed, itemised quote to benchmark everything else against. Free, no obligation, and no pushy sales calls.
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How much do solar panels cost in the UK? The 2026 average
The average solar panel installation in the UK in 2026 costs around £6,500 for a 4kW system — ten 400–450W panels, a string or hybrid inverter, mounting, scaffolding, labour and certification, with 0% VAT. Realistic quotes for that system run from about £5,500 from a good regional installer to £7,500–£8,000 from a national brand. Anything under £5,000 deserves a hard look at what’s been left out; anything over £9,000 for panels alone is paying for a sales team.
That average has moved a long way. The same system cost £12,000–£14,000 in 2012 and about £8,000 in 2019. Panels have got cheaper and more powerful — a 2026 panel produces 430–450W where a 2015 one managed 250W, so a 4kW system needs ten panels rather than sixteen, which cuts mounting, labour and roof space too. The parts that haven’t fallen are scaffolding, labour and the paperwork, which is why small systems cost disproportionately more per kW than large ones.
One other thing to settle early: every price on this page is fully installed. A panel’s shelf price (£100–£250 for a 450W module) is a fraction of the cost of getting it onto a roof safely, wired, certified and connected. If you’re comparing quotes, compare installed prices for the same specification, and check the installer is on the MCS register — without that you get no export payments, no grants and no recognised certificate, however cheap the price.
Solar panel cost by system size
System size in kW (technically kWp, kilowatt-peak) is the single biggest driver of price. Here’s what each common size costs installed in 2026, what it produces and who it suits. Click through for a full guide to each.
| System | Panels (450W) | Installed cost (0% VAT) | Cost per kW | Annual output* | Typical home |
|---|---|---|---|---|---|
| 3kW | 7 | £4,500–£6,000 | £1,500–£2,000 | 2,500–3,000kWh | 1–2 bed, low usage, small roof |
| 4kW | 9–10 | £5,500–£7,500 | £1,400–£1,900 | 3,400–4,000kWh | 3-bed semi — the UK’s most common install |
| 5kW | 11–12 | £6,500–£8,500 | £1,300–£1,700 | 4,200–5,000kWh | 3–4 bed, home in the day |
| 6kW | 13–14 | £7,500–£9,500 | £1,250–£1,600 | 5,000–6,000kWh | 4 bed, EV or high usage |
| 8kW | 18 | £9,500–£11,500 | £1,200–£1,450 | 6,800–8,000kWh | Large detached, heat pump |
| 10kW | 22–23 | £11,000–£13,000 | £1,100–£1,300 | 8,500–10,000kWh | Large home, EV + heat pump, or small business |
*Output assumes a south-ish, unshaded roof in central England; see solar panel output for how it changes with direction and region. Note the cost per kW falling from about £1,750 at 3kW to about £1,200 at 10kW — if your roof and usage justify going one size up, the extra kW is cheap. Systems above 3.68kW per phase need DNO approval before connection (G99), which a good installer handles, usually at no extra charge; larger inverters are sometimes export-limited while that goes through. Not sure which size? How many solar panels do I need works it out from your bill.
Solar panel cost by number of panels
Installers talk in kW; homeowners tend to count panels. With 2026’s standard 430–450W modules, the two translate like this:
| Number of panels | System size | Panels only | With 5kWh battery | With 10kWh battery |
|---|---|---|---|---|
| 6 panels | 2.5–2.7kW | £4,000–£5,500 | £7,500–£9,500 | — |
| 8 panels | 3.4–3.6kW | £5,000–£6,500 | £8,500–£10,500 | £10,000–£12,000 |
| 10 panels | 4.3–4.5kW | £5,500–£7,500 | £9,000–£11,500 | £10,500–£13,000 |
| 12 panels | 5.2–5.4kW | £6,500–£8,500 | £10,000–£12,500 | £11,000–£14,000 |
| 16 panels | 6.9–7.2kW | £8,500–£10,500 | £12,000–£14,500 | £13,000–£16,000 |
| 20 panels | 8.6–9kW | £10,000–£12,500 | £13,500–£16,500 | £14,500–£18,000 |
A useful sense-check against these ranges: Octopus Energy’s fixed national prices in September 2026 are around £8,600–£9,000 for 8 panels with a 5kWh battery and £11,115 for 12 panels with a 10kWh battery — squarely inside the “with battery” columns above. Our Octopus solar review takes those apart. Each panel is roughly 1.1m × 1.7m; how many panels fit on your roof shows how to count them, and solar panel sizes covers the physical dimensions and wattages on sale.
Solar panel cost by house type — 2, 3 and 4 bed
Bedrooms are a rough proxy for two things that actually set the price: how much electricity you use and how much roof you have. Here’s what each house type typically needs and pays.
| House | Typical usage | System fitted | Panels only | With battery | Saving / yr |
|---|---|---|---|---|---|
| 2-bed house or flat with roof | 2,000–2,700kWh | 3–3.5kW (7–8) | £4,500–£6,500 | £8,000–£10,500 | £450–£650 |
| 3-bed semi or terrace | 2,900–3,800kWh | 4–5kW (10–12) | £5,500–£8,000 | £9,500–£13,000 | £700–£950 |
| 4-bed detached | 4,000–5,500kWh | 5–7kW (12–16) | £6,500–£10,000 | £11,000–£15,500 | £900–£1,300 |
| 5-bed+, EV and heat pump | 7,000kWh+ | 8–10kW (18–23) | £9,500–£13,000 | £14,000–£19,000 | £1,400–£2,000 |
| Bungalow | 2,500–3,500kWh | 4–6kW (large roof) | £5,000–£8,500 | £9,000–£13,500 | £700–£1,100 — cheaper scaffolding |
The 3-bed house deserves its own answer because it’s the one most people are asking about. A 3-bed semi with a south, east or west roof will usually take 10–12 panels. Panels alone, expect £5,500–£8,000; the middle of that range, around £6,500–£7,000, is a fair price for decent-brand kit from a regional installer. With a 5kWh battery you’re at £9,500–£11,500; with 10kWh, £10,500–£13,000. At 3,500kWh a year of usage that saves £700–£950 a year without a battery and £1,000–£1,300 with one, so payback lands at seven to nine years either way. The full working is in our 3-bed house guide.
Bungalows are worth a mention because they’re often cheaper than the house-type table suggests: single-storey scaffolding is a few hundred pounds less, and the roof is usually big enough for a larger system with a better price per kW. Flats are the opposite: unless you own the roof, you’re limited to plug-in balcony solar at £400–£900.
Solar panel and battery cost
Roughly six in ten new installations now include a battery, and “cost of solar panels and battery” is one of the most-asked questions in the country. The honest answer: a battery adds £3,500–£6,000 to the job, depending on size and brand, and adds more if you retrofit it later.
| Battery size | Added cost (installed with panels) | Retrofit later | Suits |
|---|---|---|---|
| 5kWh | £3,000–£4,000 | £3,500–£4,800 | 2–3 bed, modest evening use |
| 10kWh | £4,500–£6,000 | £5,000–£7,000 | 3–4 bed, out all day, time-of-use tariff |
| 13.5kWh (Powerwall 3) | £7,000–£9,000 | £7,500–£9,500 | Large home, EV, backup in power cuts |
Fitting the battery at the same time as the panels shares the scaffolding, the electrician’s day and the paperwork, which is where the £500–£1,000 saving over adding a battery later comes from. A hybrid inverter that handles both costs a little more than a string inverter but avoids buying a second one for the battery. Whether the battery is worth its price is a separate question — our are solar batteries worth it guide answers it, what size battery stops you over-buying, and the batteries hub compares brands and prices. Batteries qualify for 0% VAT until March 2027 too, including batteries installed without panels.
Solar panel price per panel and per kW
Two different numbers get called “the price of a solar panel”, and they’re a long way apart.
- Panel only, off the shelf: £100–£250 for a 430–450W residential module. Budget Chinese brands (DMEGC, Jinko, JA, Longi) sit at the bottom; premium brands (SunPower/Maxeon, REC, Aiko) at the top. See best solar panels UK for the brand comparison.
- Per panel, installed: £550–£750 once you divide the full cost of a typical system by its panel count. That’s the number that matters, because you can’t put a bare panel on a roof.
- Per kW installed: £1,300–£1,800 for domestic systems, falling towards £1,100 at 10kW. Commercial rooftops get down to £700–£1,000 per kW at 50kW+ — see commercial solar.
- Per watt: roughly £1.30–£1.80 installed, or 25–55p for the panel alone. Useful for comparing against overseas figures, which are usually quoted this way.
The brand of panel moves a 10-panel system’s price by about £500–£1,500. That’s real money but rarely the biggest line — the installer’s margin and the inverter choice matter more. Higher-efficiency panels earn their premium only when roof space is tight.
Solar panel installation cost breakdown
Most installers quote one all-in figure. Here’s what’s inside it for a typical 4kW, 10-panel job, so you can see where the money goes and what an itemised quote should roughly look like.
| Item | Typical cost | Share | Notes |
|---|---|---|---|
| Panels (10 × 430–450W) | £1,500–£3,000 | 25–35% | Brand is the main variable |
| Inverter | £800–£1,500 | 12–18% | String £800–£1,200; hybrid £1,000–£1,500; microinverters £1,500–£2,500 — see inverters explained |
| Mounting & roof hooks | £300–£600 | 5–8% | Slate, in-roof and flat roofs cost more |
| Cabling, isolators, generation meter | £200–£400 | 3–5% | |
| Scaffolding | £600–£1,200 | 10–15% | Higher for three storeys, conservatories, awkward access |
| Labour | £1,000–£1,800 | 15–25% | 2–3 fitters, 1–2 days; see how long installation takes |
| MCS certificate, DNO, Part P, warranty admin | £150–£400 | 3–5% | Non-negotiable — without MCS, no export payments |
| Installer margin | £800–£2,000 | 10–25% | The gap between a regional firm and a national brand |
| Total | £5,500–£8,000 | 100% | 0% VAT to 31 March 2027 |
“Solar panel installation cost” on its own — labour plus scaffolding plus certification, no hardware — is therefore around £1,800–£3,400 for a normal house. That’s why buying your own panels rarely saves anything: an installer who didn’t supply the kit will still charge that, will often charge extra to warrant someone else’s equipment, and you lose the bundled discount they get from their wholesaler. How solar panels are installed walks through what those two days involve.
Want that table filled in for your own roof?
A vetted local installer will survey it, quote it line by line and stand behind the price — free, and yours to compare against anyone else’s.
Price My Roof Free →Solar panel cost by region — England, Scotland, Wales & Northern Ireland
Installed prices don’t vary much across the UK — a panel costs the same in Aberdeen as in Exeter — but labour rates, scaffolding and competition move a 4kW quote by around £500–£1,000 between regions. What varies far more is output, which is what decides whether the price is worth paying.
| Region | 4kW installed | Yield (kWh per kW/yr) | 4kW saving/yr | Payback | Notes |
|---|---|---|---|---|---|
| London | £6,500–£8,500 | 950–1,000 | £800–£950 | 8–9 yrs | Highest labour and scaffolding costs; parking permits. London guide |
| South East & East | £5,800–£7,800 | 950–1,050 | £800–£1,000 | 7–8 yrs | Oxford, Portsmouth, Southampton, Crawley |
| South West | £5,500–£7,500 | 1,000–1,050 | £850–£1,000 | 7–8 yrs | Best yields in Britain. Bristol, Bath, Wiltshire, Dorset, Bournemouth, Exeter |
| Midlands | £5,500–£7,200 | 900–950 | £750–£900 | 7–9 yrs | Competitive market. Birmingham |
| North of England | £5,300–£7,000 | 850–900 | £700–£850 | 8–9 yrs | Often the cheapest installs. Leeds |
| Wales | £5,500–£7,200 | 850–950 | £700–£900 | 8–10 yrs | Nest scheme for eligible homes. Cardiff |
| Scotland | £5,500–£7,500 | 750–900 | £600–£800 | 8–11 yrs | HES loan no longer covers solar-only; 0% VAT applies |
| Northern Ireland | £5,500–£7,500 | 800–900 | £650–£800 | 9–11 yrs | No SEG — suppliers set their own export rates |
Solar panel cost in Scotland: you’ll pay the same £5,500–£7,500 for a 4kW system, and the same 0% VAT applies; a south-facing roof in Glasgow or Edinburgh yields around 85% of one on the south coast, so payback stretches to eight to eleven years — still comfortably inside a 25-year panel life. Home Energy Scotland’s interest-free loan no longer covers standalone solar PV, so don’t let an installer build it into the sums. Solar panel cost in Wales: again £5,500–£7,200 for 4kW, yields between the Midlands and the North, and lower-income households may qualify for free measures under Nest — details in our grants guide. Wherever you are, a local installer is usually £1,000–£2,500 cheaper than a national brand for the same kit.
What moves the price up or down
Two identical-looking 4kW quotes can be £2,000 apart. These are the things that legitimately change the price — and the ones that don’t.
Adds to the cost
- Scaffolding complexity: three storeys, a conservatory under the roof, no side access — £300–£800 extra.
- Roof type: slate (+£300–£600), in-roof (+£1,000–£2,000), flat roofs (+£500–£1,000 for frames and ballast).
- Shading: optimisers or microinverters add £50–£120 per panel.
- Consumer-unit or earthing upgrades: £300–£800 in older homes.
- Premium panels or a bird-proofing kit: £500–£1,500 and £300–£600 respectively.
- Buying on finance: installer credit at 8–12% APR can add £2,000–£4,000 over ten years.
Brings it down
- Going one size up: the extra kW costs £900–£1,200, well below the average.
- Single roof face, straightforward pitch: quicker fit, one string, one scaffold lift.
- Regional installer vs national brand: £1,000–£2,500 on the same kit.
- Standard-tier panels: Jinko, JA, Longi, DMEGC perform within a few per cent of premium brands.
- Group-buying schemes: council Solar Together rounds typically land 15–25% under open-market prices when your area is running one.
- Off-season booking: installers are quietest November to February.
What doesn’t change the price: postcode-based “grants” that mysteriously expire today, “government-backed” discounts, and the difference between 25- and 30-year panel warranties. If the discount only exists while the salesperson is in your kitchen, it isn’t a discount — see solar panel scams.
Are solar panel prices going up or down?
Down for hardware, flat for installation, and with a fixed deadline that matters more than either. Panel prices fell by more than half between 2015 and 2025 and dropped again through 2025 into 2026 as global manufacturing outran demand; inverters and batteries followed, more slowly. Scaffolding, labour and certification have gone the other way with wages. Net result: the installed price of a 4kW system has drifted down a few hundred pounds a year, and there’s little reason to expect a sudden drop.
The waiting maths is simple. A 4kW system saves £700–£950 in its first year. For waiting a year to pay off, prices would have to fall by more than that plus the £325 VAT — a 15–20% drop in twelve months, which hasn’t happened in this decade. Our buy now or wait guide runs the numbers both ways.
Running costs after installation
Solar panels have no fuel and no moving parts, but “zero maintenance” isn’t quite true. Budget for these over 25 years:
| Item | Cost | How often | Notes |
|---|---|---|---|
| Inverter replacement | £800–£1,500 | Once, at 10–15 years | The one big cost; microinverters last longer but cost more upfront |
| Cleaning | £80–£200 a visit | Every 2–5 years, if at all | Rain does most of it on pitched roofs; needed for flat or dusty sites |
| Service / inspection | £100–£200 | Every 3–5 years | Optional; checks connections, isolators, mounting |
| Pigeon-proofing | £300–£900 | Once, if needed | Cheaper fitted during installation than after the birds move in |
| Monitoring | Free–£10/month | Ongoing | Most inverter apps are free; some brands charge for full history |
| Insurance | Usually £0 | — | Most home policies cover panels; tell your insurer |
Over 25 years that’s roughly £1,500–£3,000 all in — about £100 a year against savings of £700–£1,300 a year. Our maintenance guide covers what you can do yourself, and solar panel warranties explains what the installer and manufacturer are on the hook for.
How to pay less for solar panels
- Get at least two quotes on the same spec. Same panel count, named panel and inverter, same battery, MCS-method generation estimate. This alone typically saves £1,000–£2,000. We’ll match you with one vetted local installer as a benchmark; get another to compare.
- Check the grants first. Fully funded solar exists for lower-income households through ECO4 (closes December 2026) and the Warm Homes: Local Grant in England. Most homeowners don’t qualify, but check before you spend a penny — solar grants UK lists everything real (and the schemes that aren’t).
- Install before 31 March 2027 to keep 0% VAT — and install the battery at the same time if you want one.
- Size to your usage, not your roof. Every kW beyond what you can use or store earns only export rates (4–15p) rather than saving 25p. Then again, don’t under-size: the marginal kW is cheap.
- Pick a strong export tariff. Getting 12–15p rather than 4p for surplus power is worth £100–£300 a year — see SEG tariffs.
- Avoid installer finance if you can. A 0% or low-rate route (savings, mortgage further advance, a green mortgage product) beats 9.9% APR by thousands. The Government’s proposed low-interest solar and battery loans under the Warm Homes Plan are expected to be detailed late 2026.
- Watch for a Solar Together round in your council area — group buying knocks 15–25% off, though you wait months for installation.
Start with one price you can trust
We check MCS certification, consumer-code membership, insurance and reviews before an installer can quote through us. One vetted local quote, free, to measure everything else against.
Match Me With a Local Installer →Solar panel cost calculator: price your own roof in two minutes
You don’t need a survey to get within 15% of the right number. Work through these four steps with your last annual bill to hand, or let our solar panel calculator do it for you.
- Find your annual usage in kWh (it’s on the bill or your supplier’s app). No bill? 2-bed ≈ 2,400kWh, 3-bed ≈ 3,500kWh, 4-bed ≈ 4,800kWh, add 2,000kWh for an EV and 3,000–4,000kWh for a heat pump.
- Size the system: divide usage by 900 (Scotland/North: 850; South: 950). 3,500 ÷ 900 ≈ 3.9kW, so a 4kW system. Round up if you’re adding an EV or heat pump; check the roof can hold it.
- Price it: multiply by £1,500 per kW for a fair mid-range quote (£1,350 budget, £1,750 premium). 4kW × £1,500 = £6,000. Add £3,500 for a 5kWh battery or £5,000 for 10kWh. Add £500 for slate, three storeys or a flat roof.
- Estimate the saving: output (kW × 900) × your self-use share (35% without a battery, 70% with) × 25p, plus the rest × your export rate (say 12p). 4kW: 3,600kWh × 35% × 25p = £315, plus 2,340kWh × 12p = £281 → ≈ £600 a year without a battery; with one, 3,600 × 70% × 25p = £630 plus 1,080 × 12p = £130 → ≈ £760, before time-of-use savings.
Divide price by saving for a rough payback (£6,000 ÷ £600 = 10 years on those conservative assumptions; seven to nine years with a decent tariff and daytime use). If the answer looks marginal, are solar panels worth it covers the five situations where you should walk away.
Solar panel savings and payback
| System | Cost | Annual saving* | Payback | 25-year benefit** |
|---|---|---|---|---|
| 3kW, no battery | £5,000 | £500–£650 | 8–10 yrs | £9,000–£12,000 |
| 4kW, no battery | £6,500 | £700–£950 | 7–9 yrs | £12,000–£17,000 |
| 4kW + 5kWh battery | £10,000 | £1,000–£1,300 | 8–10 yrs | £13,000–£20,000 |
| 6kW + 10kWh battery | £13,000 | £1,400–£1,900 | 7–9 yrs | £20,000–£30,000 |
| 10kW + 13.5kWh battery | £20,000 | £2,000–£2,800 | 7–10 yrs | £28,000–£42,000 |
*At ~25p/kWh import and 12p export, average roof, central England. **After inverter replacement and 0.5%/yr panel degradation, assuming flat electricity prices — every price rise shortens payback. What your electricity bill looks like with solar shows the month-by-month picture, and solar panels and house value covers the resale side.
Running a business? The numbers are better still — 100% first-year tax relief, no business rates on the panels to 2035 and daytime demand that matches generation. See commercial solar panel costs, or solar for farms.
The bottom line on solar panel cost
Budget £5,500–£7,500 for a typical 4kW home system in 2026, £9,500–£13,000 with a battery, and expect the money back in seven to ten years on a system that runs for twenty-five. Bigger systems are cheaper per kW, regional installers beat national brands by £1,000–£2,500 on the same kit, and Scotland and Wales pay the same but wait a year or two longer for payback.
Prices are drifting down slowly; the VAT rate is going up on a fixed date. If your roof faces anywhere from east through south to west and you’ll be in the house for the payback period, the best price you’ll get is a fair quote installed before 31 March 2027 — not a hypothetical cheaper one in 2028.
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Solar panel cost: frequently asked questions
How much do solar panels cost in the UK in 2026?
A typical 4kW system of 10 panels costs £5,500–£7,500 fully installed with 0% VAT, and around £6,500 is the national average. Smaller 3kW systems are £4,500–£6,000, 5–6kW systems £7,000–£9,000, and a 10kW system £11,000–£13,000. Adding a 5–10kWh battery adds £3,500–£6,000. Per kW installed, expect £1,300–£1,800, falling as the system gets bigger because scaffolding, labour and paperwork are largely fixed.
What is the cost of solar panels for a 3-bedroom house?
Most 3-bed houses fit a 4–5kW system of 10–12 panels, which costs £5,500–£8,000 installed in 2026, or £9,500–£13,000 with a battery. A 3-bed semi using around 3,500kWh a year would save £700–£950 a year from a 4kW system, giving a payback of seven to nine years. The exact figure depends on roof size and direction, whether scaffolding is straightforward, and which panel and inverter brands are fitted.
How much does solar panel installation cost on its own?
Labour is around £1,000–£1,800 of a typical quote — two or three fitters for one to two days — and scaffolding another £600–£1,200. The hardware is the rest: £1,500–£3,000 for the panels, £800–£1,500 for the inverter, £300–£600 for mounting and £200–£400 for cabling and isolators, plus £150–£400 for the MCS certificate, DNO notification and electrical sign-off. Most installers only quote a single all-in price, so ask for it itemised if you want to compare fairly.
How much do solar panels cost in Scotland and Wales?
Installed prices are much the same across Great Britain — a 4kW system is £5,500–£7,500 in Scotland and Wales as in England, sometimes a little cheaper outside the South East where labour costs are lower. What differs is the output: a south-facing roof in the Central Belt yields around 800–900kWh per kW a year against 950–1,050 on the south coast, so payback in Scotland is typically eight to eleven years rather than seven to nine. Scotland’s Home Energy Scotland loan no longer covers standalone solar; Wales has the Nest scheme for eligible lower-income homes.
Are solar panel prices going up or down in 2026?
Down for the hardware, flat for the installation. A 4kW system that cost around £12,000 in 2012 costs roughly £6,500 today, and panel prices fell again through 2025 into 2026 as module oversupply continued. Labour and scaffolding are not falling. The one firm date is 31 March 2027, when the 0% VAT rate on residential solar and batteries ends and returns to 5% — adding around £325 to a £6,500 system. Waiting for cheaper panels rarely beats a year of savings plus the VAT window.
How much does a solar panel system cost with a battery?
A 4kW system with a 5kWh battery costs £9,000–£11,500 installed; a 5–6kW system with a 10kWh battery £11,000–£14,000. The battery itself is £3,500–£6,000 depending on size and brand, and adding it at the same time as the panels saves £500–£1,000 against retrofitting later because the scaffolding, electrician and paperwork are shared. Batteries also qualify for 0% VAT until March 2027, whether fitted with panels or on their own.
Prices are typical UK installed ranges for September 2026, compiled from installer quotes, published fixed-price offers and industry cost data, and are for guidance only. Your quote will depend on roof type and access, system specification, brands, location and installer. Output, savings and payback figures assume an unshaded south-east to south-west roof, ~25p/kWh import and ~12p export; tariffs and electricity prices change. 0% VAT on residential solar and battery installations applies until 31 March 2027 per HMRC. Always obtain quotes from MCS-certified installers and compare like-for-like specifications.